Re: tab-completion debug print

On Tue, Nov 27, 2018 at 06:06:06PM +0900, Kyotaro HORIGUCHI wrote:
> Hello.
>
> At Mon, 26 Nov 2018 07:08:53 +0100, David Fetter <david(at)fetter(dot)org> wrote in <20181126060853(dot)GP958(at)fetter(dot)org>
> > On Sun, Nov 25, 2018 at 11:21:51PM -0500, Tom Lane wrote:
> > > Kyotaro HORIGUCHI <horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp> writes:
> > > >> On Fri, Nov 23, 2018 at 04:32:31PM -0500, Tom Lane wrote:
> > > >>> Hm. I can see the value of instrumenting tab-complete when you're trying
> > > >>> to debug why it did something, but this output format seems pretty terse
> > > >>> and unreadable.
> > >
> > > > The reason for the minimal output was it won't disturb console so
> > > > much when stderr is not redirected. It could be richer if we
> > > > premise redirection.
> > >
> > > It seems to me this behavior would be completely unusable if it's not
> > > redirected; I don't understand why you're even considering that as an
> > > interesting option. libreadline is necessarily active when we're doing
> > > this, and it will get very confused (or at least produce a very confused
> > > display) if anything else is emitting text onto the active console line.
>
> The mess here started because I forgot about -L option of psql. I
> wouldn't do that if I knew of it.

Am I understanding correctly that currently, -L specifies a separate
log that only shows the output of queries?

If we're using that log, we'll need to rethink how best to describe
the new sub-feature, and possibly rethink how -L should function.
Tom's suggestion about recording both the catalog queries and their
result set/error messages seems in scope.

Speaking of scope, do we want something like \L (analogous to \o) for
this, or would a thing like that be fundamentally distinct?

> psql -L ~/psqldebug.log postgres

Excellent!

Do we still want this as a compile-time option, or does it make more
sense as a run-time option? I'm thinking that with \L, it might make
sense as a run-time option.

Best,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778

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